Drift diameter shrink of gate valve
If a body's passage diameter (often are the smaller valve flange joints size), called size shrinkage.
Size shrinkage can make parts, open and closed size required force decreases, can also expand the application range of components. But after sizing contraction. Fluid loss of resistance.
Some work in some departments under the condition of the departments (e.g. oil pipeline), do not use the valve size shrinkage. This is to reduce the loss of the pipeline resistance, on the other hand is to avoid size shrinkage to mechanical cleaning line after a barrier.
